Sealing plug

ABSTRACT

A sealing plug for sealing an opening in a component has a substantially annular or cylindrical shank, the shank is closed by a sealing surface, and a sealing lip is provided on the shank and having a cone-shaped configuration. The sealing lip locks in place on the rear side of the component and closes the opening. The free edge of the first sealing lip is in contact with the rear side of the component in the assembled condition. The sealing lip has at least one flexible folding zone provided thereon which is reversibly foldable such that in a folded condition of the folding zone the circumference of the sealing lip is reduced in the area of the folding zone at least one of the edge and the sealing lip.

TECHNICAL FILED

The present invention relates to a sealing plug for sealing an openingin a component, in particular a vehicle body part, including asubstantially annular or cylindrical shank which is closed by a sealingsurface, and a sealing lip provided on the shank and having acone-shaped configuration, the sealing lip locking in place on the rearside of the component and closing the opening, the free edge of thesealing lip being in contact, in particular in surface contact, with therear side of the component in the assembled condition.

BACKGROUND OF THE INVENTION

Such sealing plugs are shown for example in DE 10 2009 018 395 A1, DE 3446 151 A1 or DE 10 2009 032 243 A1.

Such a sealing plug is mounted in that the cone-shaped sealing lipthereof is inserted into the opening until the free edge of the sealinglip snaps in place on the rear side of the component. When mounting hasbeen completed, the sealing lip rests against the rear side of thecomponent to as to surround the opening and seals the opening in thisway. Since the sealing lip has a cone-shaped design and a largerdiameter than the opening, the sealing lip is deformed during assembly.Depending on the stiffness of the material of the sealing lip and thedifference between the diameter of the sealing lip and that of theopening, very high assembly forces are required for deforming thesealing lip and inserting the sealing plug into the opening. But it isnot possible to interrupt the sealing lip in order to make it moreflexible or to prevent a wave-shaped deformation because suchinterruptions would lead to the sealing lip being no longer able to bein continuous contact around the opening and therefore being no longerable to seal the opening.

The object of the invention is to provide a sealing plug which allows anassembly requiring a lower assembly force, but which still provides forthe sealing plug to be securely held in place and for the opening to bereliably sealed.

BRIEF SUMMARY OF THE INVENTION

According to the invention, a sealing plug for sealing an opening in acomponent has a substantially annular or cylindrical shank, the shank isclosed by a sealing surface, and a sealing lip is provided on the shankand having a cone-shaped configuration. The sealing lip locks in placeon the rear side of the component and closes the opening. The free edgeof the first sealing lip is in contact with the rear side of thecomponent in the assembled condition. The sealing lip has at least oneflexible folding zone provided thereon which is reversibly foldable suchthat in a folded condition of the folding zone the circumference of thesealing lip is reduced in the area of the folding zone at least one ofthe edge and the sealing lip.

The folding zone allows the circumference of the sealing lip to bereduced by applying a substantially lower force since it offers a lowerresistance to the folding-up or deformation,

In the non-assembled and fully assembled conditions, the sealing lip iscompletely closed in the circumferential direction, so that a reliablesealing of the opening is possible. But in an intermediate assemblycondition, the sealing lip is folded up in the folding zone, so that ithas a smaller diameter and can be inserted into the opening with a lowerassembly force. The folding zone causes this folding-up to occurautomatically, as it were, during insertion of the sealing plug into theopening, by the sealing lip being displaced by the edge of the opening.That is, rather than an arbitrary deformation, a systematic deformationtakes place at the folding zones, in this case a folding. The foldingzone has bending edges, for example, which allow a deformation withsignificantly lower effort.

The folding-up gives the cone of the sealing lip a greater inclination,so that the free edge of the sealing lip has a small circumference. Inan extreme case, the sealing lip can be reshaped by the folding zone toform a cylinder. The folding zones preferably allow the circumference tobe reduced at least to such an extent that it is smaller than thecircumference of the opening. In any event, owing to the folding zonethe sealing lip can be pushed through the opening with a lowerresistance since the folding zone is designed so as to allow the sealinglip to be folded up in a simple way involving small forces.

The folding zone can subsequently unfold again on the rear side of theopening, so that the sealing lip can rest against the rear side of theopening in the circumferential direction.

This allows a simple assembly of the sealing plug because the assemblyforce required is lower, and at the same time a reliable sealing of thesealing plug is ensured.

The folding zone can, for example, be folded inwards, in particularradially inwards, towards the longitudinal axis of the shank, so that inthe folded condition it does not project beyond the outer circumferenceof the sealing lip.

Depending on the size of the folding zone, in the folded condition itextends inwards towards the shank to a greater or lesser extent. If thefolding zone is made especially large or if the sealing lip is arrangedvery close to the shank, it may occur that when the folding zone isfolded inwards, it rests against the shank, which makes a furtherfolding of the folding zone more difficult. In order to rule this out,the shank may have recesses provided thereon into which the folding zoneextends in the folded condition.

The shank seals the opening together with the sealing surface and thesealing lip. In order to completely seal the opening in the installedcondition of the sealing plug, in particular in an embodiment withrecesses provided on the shank, the shank has at least one secondfolding zone provided thereon in the region of the at least one foldingzone of the sealing lip, in particular at the recesses. This secondfolding zone, in a way, closes the recess in the shank, so that theshank is completely closed in the circumferential direction and can sealthe opening. The second folding zone can be folded inwards, inparticular radially inwards, jointly with the first folding zone. Inthis way, the shank is closed in the circumferential direction, and thefolding zone of the sealing lip can still extend into the shank in thefolded condition.

Preferably, the first and second folding zones are connected with eachother, so that both folding zones are folded inwards jointly. Also, thisconnection makes sure that the sealing plug is completely closed and canreliably seal the opening.

For example, the folding zones are each formed by two folding surfaceswhich are configured substantially triangular or trapezoidal. The twofolding surfaces each have a first edge by which they are flexiblyconnected with each other, and a second edge by which they are flexiblyconnected with the sealing lip. In the folded condition, these foldingsurfaces can be in surface contact with each other, but are at leastmutually folded towards each other by the shared edge.

In a non-assembled condition, the folding zones may be completelyunfolded. But it is also possible that the folding zones, in anon-assembled condition, are pre-folded inwards, with only a slightpre-folding being required. This pre-folding simplifies the folding ofthe folding zone during insertion of the sealing plug into an opening.

In order to give the sealing surface more stability, the sealing surfacehas, for example, at least one stiffening rib provided thereon whichmore particularly is provided at the at least one recess or at thesecond folding zones on the shank. This stiffening rib, firstly,provides a support to the sealing surface, so that the latter canwithstand a higher pressure. Secondly, the shank is reinforced in thearea of the recesses or of the second folding zones. More particularly,the stiffening rib is U-shaped in cross-section, the legs of this “U”each being adapted to be connected with the shank at an edge of therecess.

In this embodiment, the folding zone folds into the stiffening rib. Tothis end, the stiffening rib includes a kind of receiving space in whichthe first and/or the second folding zone extend(s) in the foldedcondition.

To simplify assembly of the sealing plug, provision is made, forexample, for a centrally arranged pressure surface, and at least one webextends from the shank as far as to the pressure surface. This pressuresurface allows a greater assembly force to be applied to the sealingplug during assembly of the sealing plug. This web can also beconstituted by a stiffening rib, for example.

The sealing surface may be curved convexly outwards, for example, inorder to obtain a higher resistance to high assembly forces or animproved sealing in the case of high pressures.

To allow the sealing plug to be simply inserted into the opening, onlyone folding zone is required. Preferably, however, a plurality of firstand second folding zones are provided which are more particularlyarranged so as to be uniformly distributed on the circumference of thesealing plug, so that the sealing lip and the shank are, in a sense,subdivided into a plurality of sections which are each connected witheach other by folding zones, so that the sealing lip and the shank areclosed in the circumferential direction. A respective stiffening rib maybe provided in the area of each folding zone, with the stiffening ribsin such an embodiment preferably extending from a centrally arrangedpressure surface to the folding zones in a star shape.

In such a sealing plug, provision may also be made for a second sealinglip which, in the assembled condition of the sealing plug, rests againstthe front side of the component and seals the opening.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a sealing plug according to theinvention;

FIG. 2 shows a perspective view of the underside of the sealing plugfrom FIG. 1;

FIG. 3 shows a cross-section of the sealing plug from FIG. 1 in theassembled condition;

FIG. 4 shows a first detailed view of the folding zone of the sealinglip of the sealing plug from FIG. 1;

FIG. 5 shows a second detailed view of the folding zone of the sealinglip of the sealing plug from FIG. 1;

FIG. 6 shows a sectional view of the sealing plug from FIG. 1 in thearea of the folding zones; and

FIG. 7 shows a second sectional view of the sealing plug from FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1 and 2 show a sealing plug 10 by means of which an opening 12 ina component 14, for example a body part in a vehicle, can be sealed (seeFIG. 3).

The sealing plug 10 includes a substantially annular shank 16 which isclosed by a circular sealing surface 18. Provided on the outercircumference of the shank is a sealing lip 20 which can be in contactwith the rear side 21 of the component 14 and seal the opening 12 inthis way (see also FIG. 3). Provision is further made for a secondsealing lip 22 which is oriented opposite to the first sealing lip 20and can be in contact with the front side 23 of the component 14 and canadditionally seal the opening 12 in this way. Both sealing lips 20, 22have a cone-shaped configuration, the second sealing lip 22 beingoriented opposite to the first sealing lip 20.

For assembly of the sealing plug 10, the shank 16 is inserted into theopening 12 in an insertion direction E, the sealing lip 20 beingdisplaced by the edge 25 of the opening 12 and, in the process, beingdeformed such that the sealing plug 10 can be further inserted into theopening 12.

Once the sealing plug 10 has been fully inserted into the opening 12,the sealing lip 20 can unfold on the rear side 21 of the component 14 toassume its original shape again, and can circumferentially rest againstthe rear side 21 of the component 14 in a continuously surroundingmanner and seal the opening 12. In this condition, the second sealinglip 22 rests against the front side 23 of the component 14, inparticular in a pretensioned state, to form a second seal.

The sealing plugs known so far require a relatively high assembly forcefor deforming the sealing lip 20 during insertion into the opening 12.The sealing lip 20 is randomly deformed, for example in a wave shape, bythe edge 25 of the opening 12; depending on the stiffness of the sealinglip 20 or the size of the opening 12, this may require very highassembly forces.

To reduce the assembly forces, the sealing plug 10 according to theinvention includes a plurality of folding zones 24 on the sealing lip 20which are uniformly distributed in the circumferential direction.

As can be seen in FIG. 2, each of these folding zones 24 is formed bytwo folding surfaces 26 which in the embodiment shown here areconfigured to be substantially trapezoidal. A first edge 28 forms abending edge which extends substantially in the insertion direction Eand about which the folding surfaces 26 can each be swiveled towards thesealing lip 20. The folding surfaces 26 are connected with each other bya second edge 30 opposite the first edge 28 and can be swiveled inrelation to each other. The first and second edges 28, 30 are eacharranged in a plane that runs substantially through the center axis M ofthe sealing plug 10.

As can be seen in particular in FIG. 2, the shank has recesses 32provided thereon, each in the region of the folding zones 24, into whichthe folding zones 24 or the folding surfaces 26 can fold inwards, inparticular radially inwards, in relation to the longitudinal axis of theshank.

The recesses 32 have second folding zones 34 provided thereon which alsoeach consist of a pair of folding surfaces 36 each having a first edge38 that is connected with the shank 16 in a hinged fashion and having anopposed, second edge 40 connecting them with each other in a hingedfashion.

The folding surfaces 26, 36 of the first folding zones 24 and of thesecond folding zones 34 are each connected with each other by theirrespective edge 42, 44 which is the front edge in the insertiondirection E so that the recesses 32 are completely closed.

When the sealing plug 10 is inserted into the opening 12, the sealinglip 20 comes into contact with the edge of the opening 12 and is urgedradially inwards by the edge. This causes the folding zones 24 to befolded radially inwards in relation to the center axis M, that is, thefolding surfaces 26 to be swiveled towards each other and towards thesealing lip 20. The folding zones 26 thus cause the sealing lip 20 to befolded in a concertina-like fashion, as it were.

This reduces the circumference of the sealing lip 20 in the area of thefolding zones 24 such that the sealing plug 10 can be inserted into theopening 12 with a lower resistance. In an extreme case, the sealing lip20 can be deformed by the folding zones to such an extent that it has acylindrical outer circumference or at least a smaller circumference thanthe opening 12.

As can be seen in FIGS. 1 and 2, further provision is made forstiffening ribs 46 which each extend from the recesses 32 radiallyinwards as far as to a centrally arranged pressure surface 48. Thesestiffening ribs 46 serve to stabilize the sealing surface 18, so thatthe latter can withstand higher pressures or higher assembly forces.

The stiffening ribs 46 each have a U-shaped configuration, thestiffening ribs 46 each having a receiving space 50 formed therein forthe folding zones 24, 34. As can be seen in particular in FIG. 2, thestiffening ribs 46 directly adjoin the recesses 32, so that theinterruptions in the shank 16 that are formed by the recesses 32 areadditionally stabilized and are sealed, where required.

As can be seen in FIG. 5, the free edge 45 of the sealing lip 20 is notpart of the folding zone 24. But since this free edge 45 is continuouslyconnected with the folding zone 24, it is deformed together with thefolding zone 24 when the latter is folded and, in the process, the freeedge 45 is pretensioned.

Once the sealing lip 20 has been completely inserted into the opening12, this pretension and/or a pretension produced by the swiveling of thefolding surfaces 26 towards each other and in relation to the sealinglip 20 cause(s) the folding zones 24 to unfold again to assume theoriginal shape, so that the diameter of the sealing lip 20 is againlarger than the diameter of the opening 12. The sealing lip 20 can thenrest against the rear side 21 of the component 14 so as to surround theopening 12 and seal the opening 12.

Since the free edge 45 of the sealing lip 20 is not part of the foldingzones 24, a better contact of the sealing lip 20 with the component 14and, hence, better sealing of the opening 12 is ensured. But it is alsoconceivable that the free edge 45 of the sealing lip 20 is part of thefolding zones 24.

As can be seen in particular in FIGS. 4 and 5, in the embodiment shownhere the folding zones 24, 34 are slightly pre-folded inwards, so thatthey can be more easily folded away inwards during assembly of thesealing plug 10.

Since, owing to the folding zones 24, the resistance to a folding up isconsiderably lower, the assembly force is considerably lower even with acontinuous edge 45 of the sealing lip 20.

Depending on the desired assembly forces, the folding zones 24 may bearranged in any desired fashion on the outer circumference of thesealing lip 20. It should only be made sure that the circumference ofthe sealing lip 20 can be reduced by the folding zones 24 such that asimple insertion of the sealing plug 10 into an opening 12 is possible.Depending on the distance of the shank 16 from the sealing lip 20, aprovision of recesses 32 or second folding zones 34 on the shank 16 isalso not required. In particular, any stiffening ribs 46 are notrequired, either, if the sealing surface 18 has a sufficient inherentstability.

As can be seen in FIGS. 6 and 7, the sealing surface 18 is convexlycurved contrary to the insertion direction E, in order to provide itwith an additional resistance to high pressures or high assembly forces.

1. A sealing plug for sealing an opening in a component, comprising asubstantially annular or cylindrical shank, said shank is closed by asealing surface, and a sealing lip provided on the shank and having acone-shaped configuration, the sealing lip locking in place on the rearside of the component and closing the opening, the free edge of thefirst sealing lip being in contact with the rear side of the componentin the assembled condition, wherein the sealing lip has at least oneflexible folding zone provided thereon which is reversibly foldable suchthat in a folded condition of the folding zone the circumference of thesealing lip is reduced in the area of the folding zone at least one ofthe edge and the sealing lip.
 2. The sealing plug according to claim 1,wherein the folding zone can be folded inwards, in particular radiallyinwards, towards the longitudinal axis of the shank.
 3. The sealing plugaccording to claim 1, wherein the shank has at least one recess providedthereon into which the folding zone extends in the folded condition. 4.The sealing plug according to claim 1, wherein in the region of the atleast one folding zone, in particular at the at least one recess, theshank has at least one second folding zone provided thereon which can befolded inwards, in particular radially inwards, with the first foldingzone.
 5. The sealing plug according to claim 4, wherein the firstfolding zone and the second folding zone are connected with each other,so that both folding zones are folded jointly.
 6. The sealing plugaccording to claim 1, wherein the folding zones are each formed by twofolding surfaces which are configured substantially triangular ortrapezoidal, the two folding surfaces each having a first edge by whichthey are flexibly connected with each other, and a second edge by whichthey are flexibly connected with the sealing lip.
 7. The sealing plugaccording to claim 6, wherein in a non-assembled condition the foldingzones are pre-folded inwards.
 8. The sealing plug according to claim 1,wherein the sealing surface has at least one stiffening rib providedthereon which more particularly is U-shaped in cross-section and whichmore particularly is provided at the at least one recess or the at leastone folding zone on the shank.
 9. The sealing plug according to claim 8,wherein the stiffening rib includes a receiving space into which thefirst folding zone and/or the second folding zone extend(s) in thefolded condition.
 10. The sealing plug according to claim 8, wherein acentrally arranged pressure surface is provided and the at least onestiffening rib extends from the shank to the pressure surface.
 11. Thesealing plug according to claim 1, wherein the sealing surface isconvexly curved.
 12. The sealing plug according to claim 1, wherein aplurality of first folding zones and second folding zones are providedwhich more particularly are arranged so as to be uniformly distributedon the circumference of the sealing plug.
 13. The sealing plug accordingto claim 1, wherein a second sealing lip is provided which, in theassembled condition of the sealing plug, rests against the front side ofthe component and seals the opening.